Background As one of the short acting benzodiazepines， Midazolam is widely used as a premedicant before surgery，for antianxiety， and for conscious sedation.　Objective　This paper is made to give a overall statement on it.　Content　During these years， there are so many reports， at home and abroad， on midazolam's use as an anti-emetic to prevent and treat postoperative nausea and vomiting（PONV）.　Trend　Hope in the near future，midazolam， as an antiemetic，will be widely used in clinical work.